Smoke detecting and fire extinguishing system



y 1960 H. c. GRANT, JR 2, 35,135

SMOKE DETECTING AND FIRE EXTINGUISHING SYSTEM Filed Dec. 30, 1958 2Sheets-Sheet 1 VIII/l 'IIIIII4 H INVENTOR u BY 3 g ATTORNEY Ma a, 1960H. GRANT, JR

SMOKE DETECTING AND FIRE EXTINGUISHING SYSTEM 2 Sheets-Sheet 2 l n H I HI. l l l l l l H HOLD N 1 Filed Dec. 30, 1958 INVENTOR H (lgmmfl'r. BYWm M ATTORNEY 7 SMOKE DETECTING sAND FIRE EXTINGUISHING YSTEM Harry C.Grant, Jr., Ridgewood, NJ., assignor to Specialties DevelopmentCorporation, Belleville, N.J., a corporation of New Jersey ApplicationDecember 30, 19 58, Serial No. 783,927

8 Claims. cl. 169- The present invention relates to smoke detecting andfire extinguishing systems, and, more particularly, to such systems fordetecting smoke and extinguishing fire in an enclosure which isperiodically ventilated, for example, a cargo hold of a ship.

For many years, the cargo holds of ships have been protected by systemsfor detecting smoke caused by the start of a fire in the holds and forintroducing a fire extinguishing medium such as carbon dioxide into theholds to smother the fire. Generally, such a system comprises a smokedetector located in the pilot house having a plurality of unitscorresponding to the number of holds or enclosures to be protected forindicating the location of the origin of the smoke, each unit having aninlet and the detector having an outlet common to all of the inlets; aconduit running fore and aft through the middle of each hold near theceiling; one or more accumulators in the conduit into which air in thehold is drawn; a pipe leading from each conduit to an inlet of thedetector; and an exhaust fan connected to the outlet of the detector fordrawing air samples taken from the hold and through the indicatingunits. rality of receptacles containing fire extinguishing medium suchas carbon dioxide which receptacles are located below deck in thevicinity of the pipes asthey come together before running up to thepilot house, a manifold for the receptacles into which carbon dioxide isdischarged, discharge pipes each connected to one of the air samplingpipes and to the manifold, valving for the discharge pipes to determineto'which hold the carbon dioxide is to be directed, and anormally openvalve in each air sampling pipe which is closed during the discharge ofcarbon dioxide to prevent the carbon dioxide from flowing to the smokedetector and thereby direct the carbon dioxide to the conduit fordischarge through the accumulators. v

Also, for many years, it has been customary to connect a cowl ventilatorfacing fore or windward to introduce air into the holds and to connectanother cowl ventilator facing aft or leeward to withdraw air from theholds to thereby provide a ventilating system.

More recently, cargo holds have been equipped with Ventilating systemsfor periodically conditioning the air in the holds to remove odors orexcessive moisture therefrom or to change the temperature of the air.Generally, such a system comprises an apertured duct running fore andaft'at each side of the hold so that the air sampling conduit is locatedintermediate the ducts, means for introducing ventilating air into Oneofthe ducts and into the hold, and means for withdrawing ventilating airfrom the other of the ducts and from the hold. In such a system, a motordriven blower was connected to the duct for introducing the air'and/or amotor driven exhaust fan was connected to the duct for withdrawing theair.

The use of both a smoke detecting and fire extinguishing system and aventilating system of either type. described above has created aeonsiderable problem because the ventilating air in passing'through thehold disrupts the The system further comprises a plu-' Patented May 3,1960 proper functioning of the air sampling conduit to the extent thatany smoke originating in the hold downstream of the air sampling conduitand near the fore and aft walls of the hold is carried away by theventilating air and cannot reach the air sampling conduit. Consequently,more than half of the hold is unprotected by the smoke detecting systemand small fires can start and be fanned by the ventilating air to firesof a considerable magnitude before being otherwise detected. This is ahazard which cannot be tolerated by safety and fire pre ventingpractices.

Accordingly, an object of the present invention is to provide a smokedetecting system which functions properly. and is unaffected by aventilating system in the same cargo hold or other enclosure.

Another object is to provide such a smoke detecting system which isconditioned automatically while the ventilating system is, or is not,functioning.

Another object is to provide such a smoke detecting system which can becombined with a fire detecting system.

A further object is to provide such a system in a simple, practical andeconomical manner.

Other and further objects of the invention will be obvious upon anunderstanding of the illustrative embodiment about to be described, orwill be indicated in the appended claims, and various advantages notreferred to herein will occur to one skilled in the art upon employmentof the invention in practice.

In accordance with the present invention, the foregoing objects areaccomplished by providing a smoke detecting system wherein sampling airis withdrawn from the enclosure by the conduit having therein theaccumulators or the like when the ventilating system is not inoperation, and wherein sampling air is withdrawn from the duct throughwhich air withdrawn or removed from the enclosure flows when theventilating system is in operation, provision being made to switch overthe sampling operations as the ventilating system goes on or off.

A preferred embodiment of the invention has been chosen for purposes ofillustration and description, and is shown in the accompanying drawings,forming a part of the specification, wherein:

, Fig. l is a schematic plan view of a ships cargo hold provided withventilation and equipped with a smoke detecting and fire extinguishingsystem in accordance with the present invention. g

Fig. 2 is an enlarged fragmentary sectional schematic view taken alongthe line 2-2 on Fig. l. Fig. 3 is an enlarged fragmentary sectionalschematic view taken along the line 3--3 on Fig. 1.

Fig. 4 is a sectional view of one form of control valve for the system.

Fig. 5 is a wiring diagram of the circuit for energizing the motor of ablower and/or an exhaust fan including Referring to Fig. 1 of thedrawings in detail, there is shown a ships cargo hold providing anenclosure 10, which is ventilated and is protected by a smoke detectingand fire extinguishing system.

Ventilation is provided by a perforated duct 11 at one side of theenclosure for introducing fresh air into the enclosure andby a secondperforated duct 12 at the opposite side of the enclosure for withdrawingair from the enclosure. Each duct has one or more rows of slits orperforations 14 which preferably face the middle of the enclosure. Freshair is supplied to the duct 11 by a pipe 15 which is connected theretoand extends upwardly to above deck and has a shield 16 at its upper end(Fig. 2) for preventing waves and spray from entering the same. A motordriven fan or blower 17 is positioned in the pipe 15 at a suitablelocation. The air supplied to the I ensures enclosure is. removed fromthe duct 22 by a pipe 18 deck and, like the pipe 15, has a shield 16 atits upper end (Fig. 3). A motor driven exhaust fan 19 is posi-' tionedin the pipe, 1 8; at a. suitable location.

- Referringagain to Fig. 1, there also is shown a smoke detecting systemwhich is arranged in a conventional manner and generally comprises asmoke detector 20-having; a plurality of units 21, four being shown,corresponding to the number of enclosures It to be protected forindicating the. enclosure in which smoke is detected, each unit 21having and inlet 22 and the detector 20 having an outlet 24 common toall of the inlets; a conduit 25 preferably' running fore and aft throughthe middle of the enclosure near the deck above; one or moreaccumulators 26 in. the conduit 25 into whiclrair from the enclosure canenter, two accumulators being shown which may be of the type shown inUnited States Patent'Reissue No. 22,047; a pipe including a section 27connected to conduit 25 and a section 28 leading to the inlet 22 0f theunit 21 associated with the enclosure; and an exhaust fan 29 connectedto the outlet 24 of the smoke detector for withdrawing air samples fromthe enclosure and through the smoke detector.

There is further shown a fire extinguishing system 4 which is alsoarranged in aconventional manner and generally comprises a supply ofliquefied carbon dioxide 39, such as a bank of cylinders; a; manifoldiiconnected to the bank of cylinders having a plurality of valvecontrolled outlets 32 corresponding to the number of enclosures .10; adischarge pipe 34 for connecting the corresponding outlet 32 and pipesection 28; and a valve 35 in the pipe section 28 having an inlet towhich the dis charge pipe 34 is connected.

The valve 35 is constructed and arranged to normally pennit sampling airto be withdrawn from-the enclosure and, upon detection of smoke or tire,to be positioned to shut off flow communication between the smokedetector and the enclosure and to establish how communication betweenthe discharge pipe 34and the pipe section so that carbon dioxide can beintroduced 'into the enclosure to extinguish the fire. If desired, themanifold 31, the valved controlled outlets 32, the discharge pipesection and the valves. 35 may be arranged in a valve. assembly such asshown in United States Patent No. 2,661,765.

-While the ventilating system has been illustrated and described withreference to using both a blower and an exhaust fan, it will be apparentthat either only a blower and an air outlet oronly an exhaust fan and anair inlet could be used as the means for introducing air into theenclosure and for removing air therefrom.

' The. ventilating system and' the smoke detecting system,

as so far described, each would function in its intended manner, butthese systems cannot be used together without causing the smoke detectorto be rendered ineffective due to. the difficulties already described.These difficulties are .overcome by providing an arrangement forsampling the air removed from the enclosure and passing through theventilating duct 12 while the ventilating system is in operation.

As shown in Fig. 1, such an arrangement comprises a direction valve 36having an inlet 37 in fluid flow communication with the enclosurethrough the pipe section 27, the conduit 25 and the accumulators 26; aninlet 38 connected by pipe 39.to the duct-12; an outlet or port &0.connected to the pipe section 28; and a movable flow control member,described hereinafter, for establishing fluid flow communication betweenthe inlet 37 and the outlet 40, when the ventilating system is notoperating,

and for establishing fiuid flow communication between the inlet 38 andthe outlet 49, when the ventilating system is operating.

The pipe 39 preferably is connected to the duct 12; under the pipe 18(Fig. 3), and. has a downwardly facing inlet 33 at'va level above theperforations 14 in the duct,

for entraining smoke laden air drawn into the duct at any point alongthe length thereof. In practice, the suction in the pipe 39 created bythe exhaust fan 29 is greater than the suction or draft in the pipe 18,whereby sufficient sampling air will be withdrawn from the duct 12 toassure the detection of smoke therein.

in order to prevent the loss of fire extinguishing medium through thepipe 39, the duct 12 and the pipe 13 to the atmosphere while the inlet33 and the outlet 40 are connected during operation of the ventilatingsystem, a normally open floating check valve 41 may be connected in thepipe section 28near the outlet 46 which is adapted to close when fireextinguishing medium is discharged into the pipe section 28. The blockedfire extinguishing medium may be by-passed through a normally closedpoppet valve 42 connected to the pipe section just downstream of thecheck valve 41 in the direction of how of sampling air and may bedischarged directly into the enclosure from the outlet of the poppetvalve or may be discharged into the enclosure through the accumulators26 by connecting the outlet of the poppet valve by a pipe 44 to theaccumulator conduit 25.

In the event the ventilating system includes electric motor driven fansand additional wiring to each enclosure can be tolerated, the directionvalve 36 could be under the control of a solenoid arranged in the motorenergizing circuit to position its flow controlling member to sample theair in the duct 12 when the motors are energized and to sample air inthe enclosure when the motors are tie-energized.

v However, on board ship where wiring is desired to be kept at aminimum, the direction valve 36 may be controlled in response to theflow of air from the pipe 15 into the duct 11 byconnecting one end of aflow sensing i pipe 45 m the duct 12 having an inlet 4-6 directly underwill not interfere to suck air at maximum negative pressure therethroughand by connecting the other end of the sensing pipe to a control devicefor the valve 36 in the manner about to be described.

In Fig. 4:, a preferred direction valve 36 is shown which is responsiveto a suction or negative pressure operated device. 47. The valvecomprises a body 48 in which are formed the inlets 37 and 38 and theoutlet 40, a valve seat 49 between the inlet 37' and the outlet 40, avalve seat 50 between the inlet 38 and the outletdil, a valve member 51for the seat 49, a valve member 52. for the seat 50, and a slidablymounted rod 54 on which the valve members are mounted having one end 55extending outwardly of the valve body.

I The valve member 51 has a larger efi'ective area than the valve member52, whereby the pressure of the fire extinguishing medium, whendischarged into the port 4d, will ovecome the force exerted by thenegative pressure of the device 47' and will shift the valve member 51towards the left as viewed to shut ofi communication between. the port40 and the inlet 33. This prevents the loss of fire extinguishing mediumbyway of the duct 12 in event the fire extinguishing medium was releasedprematurely, that is, before the exhaust fan was stopped.

' The valve 36; when constructed as just described eliminates'the needfor the, valves. 41 and 42.

The pressure responsive device 47 comprises a casing 56, a pressuresensitive element 57 movably mounted in the casingandsecured to the end55 of the rod and dividing the casinginto' chamber sections 53 and 5?, avent 60 for the, chamber section 58 through which the rod end 55extends, an. opening 61 for the chamber section 59 to which the, sensingpipe is connected, and a light spring 62 for urging the valve member 51off its seat and the valve member 52 on its seat.

, The devicje.,47 is shown in the position it assumes when the.ventilating. system is. in operation, that is, with the exhaust, fan 19creatingsuction. to. drawthe. element 57 and the rod 54 to the right, asviewed, in opposition to the spr ng, whereby flow communication isestablished between the exhaust duct 12 and the smoke detecting system.When the exhaust fan is shut down, the pressure in the chamber section59 goes to atmospheric and the spring 62 is effective to shift the valvemembers to establish communication between the enclosure and the smokedetecting system.

In normal practice, the motors for the blower 17 and the exhaust fan 19,if operating at the time smoke is detected, should be shut down beforefire extinguishing medium is discharged into the enclosure, becauseotherwise the fire extinguishing medium would be withdrawn by theventilating system through the apertures 14 in the 1 exhaust duct 12even if the valve member 52 is seated.

Because, in the excitement of a fire being detected, an establishedroutine of operations may be performed improperly, particularly byinexperienced operators, the present invention provides an arrangementfor automatic shut down of the motors in response to the-release of thefire extinguishing medium.

In Fig. 5, one way of accomplishing this is shown. For example, themotor energizing circuit may comprise a motor M for the blower and/orexhaust fan, a' source of power P, a master or control switch 64, anormally closed safetyswitch 65 connected in series with the switch 64,and a pressure operated device 66 for opening the switch 65. i I

The device 66 comprises a cylinder 67, a piston 68 in the cylinder, arod 63 carried by the piston and adapted to be extended outwardly of thecylinder to engage the switch 65, and open the same, a spring 69 forretracting the piston rod, and a pipe 70 having one end connected to.the cylinder in piston driving relation and having its other endconnected to the pipe section 28 (Fig. l). The pipe 70 can pass throughthe ducts 11 and 12 and the pipes 15 and 18 to the devices 66.

Thus, when the motor is energized with the switches 64 and 65 closed asshown and fire extinguishing medium is releasedprernaturely, the device66 is effective to open the switch 65 and thereby de-energize'the motor.

"From the foregoing description, it will be seen that the presentinvention provides a novel and useful arrangement which enablesenclosures to have ventilation and at the same time be protected by asmoke detecting and fire extinguishing system. The invention can beembodied in newly constructed enclosures, enables enclosures protectedby a smoke detecting and fire extinguishing system to now be equippedwith ventilation, and enables ventilated enclosures to now be equippedwith a smoke detecting and fire extinguishing system;

- It will also be understood that the present invention can be utilizedin ventilated enclosures where only smoke detection is required andthe'fire is extinguished by other means than a total flooding carbondioxide fire extinguishing system as described herein.

,As various changes may be made in the form, con! struction andarrangement of the parts herein, without departing from the spirit andscope of the invention and without sacrificing any of its advantages, itis to be understoodithat all matter herein is to be interpreted asillustrativerandnot-in any limiting sense.

I claim:

= .1. Ina smoke detecting system for an enclosure, the combination ofmeans for introducing ventilating air into the enclosure, means forwithdrawing air from the enclosure, conduit means'for withdrawingsampling air from the enclosure located intermediate said ventilatingair introducing and withdrawing means, conduit means for withdrawingsampling air from saidventilating air withdrawingrrieanasmoke detectingmeans through which sampling air is passed, valve means having a pair ofinlets each'in fluidflow connection with one of said conduit means andhaving an outlet, and means for establishing a fluid flow connectionbetween said outlet and said 6 smoke detecting means, said valve meansincluding a flow control member for selectively establishing fluid flowcoin munication between one of said inlets and said outlet and forpreventingfluid flow communication between said other inlet and saidoutlet, said control member being normally positioned to establishcommunication between said outlet and said inlet connected to saidenclosure air sampling conduit means and being operable during the flowof ventilating air to establish communication between said outlet andsaid inlet connected to said ventilating air sampling conduit means.

2. In a smoke detecting system for an enclosure, the combination ofmeans for introducing ventilating air into the enclosure, means forwithdrawing air from the enclosure, conduit means for withdrawingsampling air from the enclosure located intermediate said ventilatingair introducing and withdrawing means, conduit means for withdrawingsampling air from said ventilating air withdrawing means, smokedetecting means through which sampling air is passed, valve means havinga pair of inlets each in fluid flow connection with one of said conduitmeans and having an outlet pipe means for establishing a fluid flowconnection between said outlet and said smoke detecting means, saidvalve means including flow control means for selectively establishingfluid flow communication between one of said inlets and said outlet andfor preventing fluid flow communication between said other inlet andsaid outlet, means for normally positioning said control means toestablish communication between said outlet and said inlet connected tosaid enclosure air sampling conduit means, and means operable by '.heflow of ventilating air for positioning said control means to establishcommunication between said outlet and said inlet connected to saidventilating air sampling conduit means. I

3; In a smoke detecting system for an enclosure, the combination ofmeans for introducing ventilating air into the enclosure, means forwithdrawing air from the enclosure-,=conduit means for withdrawingsampling air from the enclosure located intermediate said ventilatingair introducing and withdrawing means, conduit means for withdrawingsampling air from said ventilating air withdrawing means, smokedetecting means through which sampling air is passed, valve means havinga pair of inlets each in fluid flow. connection with one of said conduitmeans and having an outlet, means for establishing a fluid flowconnection between said outlet and said smoke detecting means, saidvalve means including 'a flow control member for selectivelyestablishing fluid flow communication between one of said inlets andsaid outlet and for preventing fluid flow communication between saidother inlet and said outlet, a spring for normally positioning saidcontrol member to establish communication between said outlet and saidinlet connected to said enclosure air sampling conduit means, and apressure sensitive element operable during the flow of ventilating airto position said control member to establish communication between saidoutlet and said inlet connected to said ventilating air sampling conduitmeans.

4.- Ina smoke detecting and fire extinguishing system for an enclosure,the combination of means for introducing ventilating air into theenclosure, means for withdrawing air from the enclosure, conduit meansfor withdrawing sampling air from the enclosure located intermediatesaid ventilating air introducing and withdrawing means, conduitmeans forwithdrawing sampling air from said ventilating air withdrawing means,smoke detecting means through which sampling air is passed, valve means7 having a pair of inlets each in fluid flow connection with one of.said conduit means and having an outlet, means for establishing a fluidflow connection between said outlet and saidsmoke detecting means, saidvalve means, including a flow control'member for selectivelyestabmunication between said other inlet and said outlet, at source offire extinguishing medium under pressure ineluding means connected fordischarging the medium into the enclosure, said control memberbeingnormally positioned to establish communication between said outletand said inlet connected to said enclosure air sampling conduit means,and being operable during the flow of ventilating air to establishcommunication between said outlet and said inlet connected to saidventilating air sampling conduit means, and means operable during thedischarge of fire extinguishing medium in response to the pressurethereof to prevent entry of the medium into the inlet connected to saidventilating air sampling conduit means.

5. in a smoke detecting and fire extinguishing system for an enclosure,the combination of means for introducing ventilating air into theenclosure, means for withdrawing air from the enclosure, at least one ofsaid means including a motor driven fan, conduit means for withdrawingsampling air from the enclosure located intermediate said ventilatingair introducing and Withdrawing means, conduitmeans for withdrawingsampling air from said ventilating air withdrawing means, smokedetecting means through which sampling air is passed, valve means havinga pair of inlets each in fluid flow connection.

with one of said conduit means and having an outlet, means forestablishing a fluid flow connectionbetween said outlet and said smokedetecting means, said valve means including a flow control member forselectively establishing fluid flow communication between one of saidinlets and said outlet and for preventing fluid flow communicationbetween said other inlet and said outlet,

a source of fire extinguishing medium under pressure including meansconnected for discharging the medium into the enclosure, said controlmember being normally positioned to establish communication between saidoutlet and said inlet connected to said enclosure air sampling conduitmeans, means responsive to the flow of ventilating air to establishcommunication between said-outlet and said inlet connected to saidventilating air sampling conduit means, a normally closed pressurevoperated? switch for said motor. driven fan, and a fluid flow connec--tion between said switch and said fire extinguishing medium dischargingmeans for opening said switch in response to the pressure of the mediumupon discharge thereof.

6. In a smoke detecting and fire extinguishing systemfor an enclosure,the combination of means for introducing, ventilating air into theenclosure, means for withdrawing air from the enclosure, at least one ofsaid means including a motor driven fan conduit means for withdrawingsampling air from the enclosure located intermediate said ventilatingair introducing and withdrawing means, conduit means for withdrawingsampling air from said ventilating air withdrawing means, smokedetecting means through which sampling air is passed, valve means havinga pair of inlets each in fluid flow connection withone of said conduitmeans and having an outlet,means for establishing a fluid flowconnection between said outlet and said smoke detecting means, saidvalvemea'ns including aflow control member for selectively estab lishingfluid flow communication between one ofsaidinlets and said outlet andfor preventing fluid flow com munication between said other inlet andsaid outlet, a source, of fire extinguishing medium under pressure iIi-'cludingrneans connected for discharging the medium intd the enclosure,said control member being normally po'si tioned to establishcommunication between said outlet" and said inlet connected to saidenclosure air sampling conduit means, means responsive to the pressureof the fire extinguishing medium upon discharge thereof to shut oficommunication to said ventilating air sampling conduit means from saidoutlet and said enclosure, a normally closed pressure operated switchfor said motor driven fan, and a fluid flow connection between saidswitch and said fire extinguishing medium discharging means for openingsaid switch in response to the pressure of the medium upon dischargethereof. 7

7, In a smoke detecting and fire extinguishing system for an enclosure,the combination of means for intro ducing air into the enclosure forventilating the enclosure, means for withdrawing air from the enclosure,conduit means for withdrawing sampling air from the enclosure locatedintermediate said ventilating air introducing and withdrawing means,conduit means for withdrawing sam pling' air from said ventilating airwithdrawing means, smo e detec ng mea s r h which mp air passed, valvemeans having a pair of inlets each in fluid flow connection with one ofsaid conduit means and having an outlet, pipe means for-establishingafluid flow connection between said outlet and said smoke detectingmeans, said valve means including flow control means for selectivelyestablishing fluid flow communication be tween one of said inlets andsaid outlet and for preventing-fluid flow communication'between saidother inlet and said outlet, sai d control means being normallypositioned to establish communication between said outlet and said inletconnected to said enclosure air sampling conduit means and beingoperableduring the flow of ventilating air to establish communicationbetween said outlet and said inlet connected to said ventilating airsampling conduit means, receptacle means for fire extinguishing mediumunder pressure, a pipe for establishing fluid flow communication betweensaid receptacle,

duce fire extinguishing medium into said pipe means,-

outlet ineans in said pipe means between said last mentioned valve meansand said outlet, said outlet means being infiuid' flow communicationwith the enclosure and including a normally closed valve for introducingfire extinguishing medium into the enclosure upon opening thereof, and anormally open valve between said outlet and' said outlet means forpreventing flow of fireext'inguishing medium to said outlet upon closingthereof in response to the discharge of the medium.

8. In a ventilating and fire extinguishing system for an enclosure, thecombination of means for introducing ventilating air into the enclosure,means for withdrawing air from the enclosure, at least one of said meansin? eluding amotor driven fan, a source of fire extinguishingmediumunder pressure including means connectedfor discharging the medium into.the enclosure, a normally closed switchand a control switch adapted tobe closed t'o' effect operation of said motor driven fan, a pressureoperated d'evice for opening said normally closed switch, and a fluid'fl'owconnected between said device and said fire extinguishing mediumdischarging means fdr efiecting operation of said device in response tothe pressure of the medium, whereby, upon-discharge of the medium,operation or said motor driven fan ceases.

References Cited in the file of this patent UNITED STATES PATENTS B01116Man-28, 1950

